The inventive concepts described herein relate to an analog-digital converter, and more particularly, relate to an analog-digital converter capable of reducing a power and a power saving method thereof.
An analog-digital converter may be a device for converting an analog signal into a digital signal. For example, analog-digital converters may include a successive approximation register analog-digital converter (hereinafter, referred to as SAR-ADC) that operates in an asynchronous manner. The SAR-ADC may perform a conversion operation (N being an integer) N times within a predetermined period of time. That is, the SAR-ADC may perform an operation for converting an analog signal into a digital signal N times.
However, N conversion operations may not be performed constantly due to a level of an input signal. Thus, the N conversion operations may be ended within a time shorter than a predetermined time of the SAR-ADC.
The SAR-ADC may conduct a normal operation in which a power is consumed constantly during a predetermined period of time. However, an asynchronous analog-digital converter such as the SAR-ADC may still consume a power at a period in which analog-to-digital conversion is not performed.